There is a system that performs merchandise registration or inventory management using a code symbol, such as a bar code, or other two-dimensional code, attached to merchandise. This system type uses an optical reader for optically reading a code symbol.
There is also a system that performs merchandise registration or inventory management using a wireless tag that is attached to merchandise. This system type uses a wireless tag reader for wirelessly reading information of a wireless tag.
In addition, there is also a system that performs merchandise registration or inventory management using both a code symbol and a wireless tag. However, with this system type, when code symbols are attached only to some articles of merchandise and wireless tags are attached only to some other articles of merchandise, an operator needs to change between using an optical reader and the wireless tag reader. For example, with respect to the merchandise to which the code symbol is attached, the operator must hold the code symbol in front of the optical reader. With respect to the merchandise on which the wireless tag is attached, the operator moves the wireless tag to within a reading range of the wireless tag reader to read the wireless tag.
Switching between an optical reader and a wireless tag reader can be troublesome. Therefore, a wireless tag reader including an antenna apparatus which does not hinder reading of the code symbol by an optical reader has been devised.
An example thereof is an antenna apparatus with a rectangular opening provided at a central portion of a substrate. On the substrate, four elements of an antenna are disposed in a rectangular shape. An optical reader can read a code symbol through the opening. With such a structure, the antenna does not hinder the functioning of the optical reader.